When a terminal passes a propagation shadowing region, for example, a tunnel where a receiving channel status is poor, and the like, while radio data of a real-time streaming type such as a voice, an image, and the like is transmitted over a mobile communication network, a mobile broadcasting network, and the like, continuous data loss may occur whereby a temporary service disconnection may occur.
Various error correction schemes have been widely used as technology to overcome a degradation in the quality of service that may occur due to continuous data loss of a broadcasting receiving terminal.
An error correction scheme enables a receiving terminal to recover lost data by additionally generating parity data for error correction such as a forward error correction (FEC) and the like and by transmitting the parity data to the receiving terminal.
For example, in the case of a FEC technology for a standardized voice and image multimedia service, a transmitting server may generate a single FEC source block by collecting Internet Protocol (IP) packets carrying an encoded video, voice, character data, and the like, based on a symbol unit, and then may calculate FEC parity with respect to the collected data of the FEC source block. The calculated FEC parity data and an IP data packet may be independently transmitted via separate logic channels. When a partial loss of an IP packet is detected due to a transmission error and the like, the receiving terminal may employ a block coding error correction scheme of recovering the lost IP packet using the received FEC parity data.
However, the loss recovery capability of the aforementioned error correction schemes is generally in proportion to an amount of generated parity data.
When a large amount of data packets is lost due to a continuous burst loss and the like in a radio channel, a large amount of parity data may need to be transmitted together with data in order to prevent a service disconnection from occurring due to the continuous burst loss. To transmit the large amount of parity data together with the data may increase a transmission bit rate and decrease the coding efficiency.
In particular, in the case of a wireless data network with a limited available bandwidth, when a significantly large number of bandwidths are assigned to transmit parity data, a transmission bit rate may need to be reduced by decreasing the number of video stream services that can be provided, or by decreasing the quality of video service.
Accordingly, there is a need for a seamless service technology that may minimize a consumption of a bandwidth used for parity data transmission, and may continuously guarantee a streaming service even in a link outage circumstance and the like.